After a few months of promises following nearly universal complaints, Microsoft released massive firmware updates for their popular and well-reviewed Surface Pro 4 and Surface Book machines. The updates are intended to resolve a number of issues primarily revolving around the machines' ability to enter the proper sleep state along with issues relating to the Intel HD display drivers.
My own Surface Pro 4 suffered from a number of the problems that the update is supposed to fix. Here's a quick list of the main issues I was experiencing, and the results after applying the updates.
Inability to enter sleep
No matter how I tried to put it to sleep -- selecting Sleep from the power options, pushing the physical power button (which is set to put the machine to sleep), or closing the Type Cover -- my unit simply would not enter a sleep mode that that resulted in an expected level of battery savings. My machine would burn 6-7% battery life each hour and ran quite warm when it was "asleep." I never put mine in a case while sleeping for fear that it would wake up and overheat, but many users who did so complained of just that phenomena.
My Surface Pro 4 will now enter what appears to be the correct sleep state. Battery life while sleeping is now much more reasonable. For example, I put my machine to sleep at 12:30am yesterday morning at 100% charge and set to not hibernate. The Surface Pro 4 woke up without a problem this at 11:00am, cool to the touch and with 87% battery life remaining. All settings were at their default (except for being set not to hibernate), including having WiFi set to stay turned on while sleeping.
That's about 1%/hour while sleeping, a dramatic improvement from the 6-7%/hour I was experiencing prior to the update. It's not iPad-like sleep performance -- my iPad Air 2 will typically be at 99% the next morning when I put it away at 100%. However, the Surface Pro 4 isn't an iPad, and so that's likely perfectly acceptable performance for a machine running an Intel Core i5 CPU.
Dysfunctional Type Cover
My Type Cover would often fail to respond when the machine was brought out of whatever sleep state it was in. I'd need to disconnect and then reconnect the Type Cover to get it working.
Simply put, my Type Cover hasn't suffered once from the disconnection issue since applying the update. This issue appears to be completely fixed, at least on my machine.
Black screen on waking from sleep
When waking up or restarting from hibernation, the display would sometimes remain off even though the machine was clearly running -- as evidenced by the infrared camera turning on so I can be logged in via Windows Hello. My method for resolving this issue was to hit the Win-P key to apparently cycle through the various external display options until returning to the internal display, which would then turn on.
I haven't had a single recurrence of the non-responsive display when resuming from sleep. That issue, too, seems to be resolved.
Overall, I think this is a good update that fixes the most glaring issues with the Surface Pro 4 -- at least for me and for many people in the various forums I've visited. As far as whether or not I'd trust slipping my sleeping Surface Pro 4 into a case and travelling with it, I'll answer this way: I'm not comfortable putting any non-mobile device into a case without hibernating first or shutting down.
My SP3 occasionally spontaneously woke up from sleep even after its own months of updates, and my MacBook Air has done the same. In fact, I once pulled out the MacBook Air from a case and it was so hot that I was surprised it hadn't burst into flames. And so, I'm not sure any machine can be trusted to stay asleep, and I certainly don't consider this particular issue to be specific to the Surface Pro 4. I'll continue my practice of hibernating or shutting down before sticking mine into a case.
In conclusion, I think that Microsoft has finally hit on a set of firmware and drivers that provides for a stable device and turns the Surface Pro 4, at least, into something much closer to the high-end hero machine that Microsoft intends. I'll have to keep testing mine to see if battery life will improve following the updates -- that remains a weakness so far. In the end, I'm finally pleased that I upgraded from my Surface Pro 3, and hopefully, can stop worrying about the machine's issues and get on with using it as my main portable productivity device.